LA JOYA — From the bed of a red pickup Thursday, ACLU leaders called for an independent look into a shooting that killed two immigrants, as the Texas Department of Public Safety announced the agent who discharged his weapon is back at work.

Tactical flight officer Miguel Avila has been reassigned to administrative duties pending the outcome of an investigation, DPS officials said.

Two Guatemalan men died and a third was injured Oct. 25 when Avila opened fire on a red pickup, like the one used in Thursday's vigil for the deceased.

The agent believed he was firing at a truck carrying a drug load and attempted to disable it, DPS reported.

The Texas Rangers, an elite arm of the DPS, charged with investigating major crimes, public corruption, officer-involved shootings, and border security operations, are leading the inquiry.

“According to news reports, these men were merely passengers in a truck pursued by law enforcement and not threatening officers nor engaged in any known criminal activity,” ACLU Executive Director Terri Burke wrote in the letter hand-delivered to DPS Director Steve McCraw. “Nevertheless, deadly force was employed. If the facts as reported are true, this use of deadly force was illegal and unconstitutional.”

Area civil rights groups gathered at a rural intersection near the shooting to decry these fatalities as well as some 18 others that have occurred in the area during border enforcement operations since 2010.

“We are alarmed by the overall culture of violence that is permeating this area by law enforcement agencies,” said Burke, who called for an agency other than the Rangers to investigate the shooting. “There is an attitude that seems to signal no regard for human life. They shoot first and ask questions later.”

On Thursday, DPS said the 14.3-mile pursuit ended within 2.6 miles of two elementary schools “at a time of day when the children are typically released from school, posing an immediate threat to the school children and motoring public.”

“Although it is very tragic that two lives were lost, had the vehicle continued recklessly speeding through the school zone, any number of innocent bystanders or young lives could have been lost or suffered serious bodily injury,” McCraw said in a news release.

“There have been any number of people providing speculative commentary and opinions about this case, most of which has no basis in fact, and I would ask that they withhold judgment until the investigation is completed and reviewed by the district attorney and grand jury.”

According to reports, state game wardens spotted the suspicious truck traveling along an unpaved road and called in the DPS after the driver continued attempting to evade them for 6.8 miles.

“The truck was traveling at a dangerously high rate of speed. The vehicle appeared to have a typical ‘covered' drug load in the bed of the truck, based upon numerous similar high speed pursuits that have previously taken place in the area,” DPS said in a press release, providing maps to show the track of the Oct. 25 pursuit.The suspected driver, a 14-year-old Mexican citizen, was briefly detained but released to his grandmother. A juvenile court judge issued a warrant for him, but as of Thursday he was at large.

The truck's passengers were all residents of the same town in Guatemala and all suspected of being in the country illegally. The deceased were identified as Marco Antonio Castro and José Leonardo Coj Cumar. Each left behind children and an interest-bearing smuggling debt of more than $5,000.

Guatemalan Consul Alba Cáceres said the surviving immigrants told her the truck bed's covering, described as a dark blanket, had blown off enough that people were visible.

DPS says the covering remained intact.

About two dozen civil rights advocates gathered in La Joya Thursday, said prayers and chanted: “We are all immigrants.”

“Only on suspicion that they were up to something, only suspecting that they were armed, they were gunned down at a distance of about 500 feet from the air,” said Michael Seifert of La Unión Del Pueblo Entero. “It sounds like war to me, but we're not at war..”

Cáceres said she has yet to receive autopsy results or death certificates needed to repatriate the bodies of the two men killed.

“We understand that they were in the country illegally, that the officials were doing their jobs, but why did they do this?” she said. “We need to have someone be able to explain why the children of these men lost their fathers.”

Meanwhile, two Texas legislators who sit on a House committee with oversight over DPS have asked its chairman to convene a hearing on the matter immediately.

Rep. Lon Burnam, D-Fort Worth, and Rep. Armando Walle, D-Houston, said they want the committee to review the trooper's conduct and the agency's policy on firing at moving vehicles.

“The fact of the matter is neither human trafficking nor drug trafficking deserves the death penalty without a trial,” Burnam said. “The two people who were killed are guilty of a misdemeanor.”